Problems with TM Research
Just a thought regarding the discussion of the lack of much systematic evidence for negative effects of TM. I've characterized these three points as "asymmetries"--imbalances, if you prefer, that potentially can lead to gaps in evidence and understanding.
Asymmetry #1: You Won't See It If You "Know" It Isn't There
Any piece of research employs one or more measures or indicators. Indicators are designed by researchers to be sensitive to variation in certain phenomena. A given study can only include indicators for phenomena conceived in advance by the researchers to be of potential interest. If there is no indicator for phenomenon "X" -- that is, if the researchers are not interested in X or believe that X can't happen -- then it is highly unlikely that evidence for X will emerge from the study.
>From my conversations with them, TM researchers firmly believe that there are absolutely no negative effects from TM practice. Their research is not designed to be sensitive to, and contains no indicators for, negative effects. They are then highly unlikely to find any.
Asymmetry #2: Infrequency of Negative Effects
There is a natural asymmetry that works against detecting negative effects from TM. Practitioners not experiencing negative effects greatly outnumber those who have experienced negative effects. (Even those convinced that there are negative effects agree that they are relatively infrequent.) While this does not diminish their importance nor relieve the TM organization of the responsibility of dealing with the problem, it does make these effects more ethereal from the researcher's standpoint. They are very difficult to measure, and their source or etiology even more so. If there's an actual casualty rate of, say, 2%, then to measure this reliably would require careful study of at least several thousand meditators, maybe more. And this doesn't begin to address the etiology problem.
Asymmetry #3: Who Conducts the Research and Who Pays For It?
Who sponsors research on TM? Mostly the TM organization. Who conducts research on TM? Almost exclusively researchers having a tremendous vested interest--material, psychological, professional and social--in the outcomes of their research.
Historically, this state of affairs has proven to be a recipe for biased results. [Suggested reading: "Betrayers of the Truth" by William Broad and Nicholas Wade--although they over-generalize their observations to all of science.] Bringing us back to the first point, how many TM researchers would you guess have conducted studies making a serious effort to detect and characterize negative effects of TM? How much money would you guess the TM organization has invested in such research? How many grant proposals to external funding sources for carrying out such research would you guess TM researchers have submitted?
>From a purely scientific standpoint (i.e., setting aside all ethical issues), TM researchers have a "theory" (well, a set of conjectures anyway) and a program of study aimed at accumulating verifications. This is common practice, especially in the social and behavioral sciences, and considered acceptable by the majority (even if not by me). The best method of testing hypotheses, however, is to try your hardest to disprove them--not merely to verify them. If they survive the most stringent of tests, you can be that much more confident in their validity.
So what if TM researchers never seek to disprove their claims but only to verify them? That's where the collective aspects of science comes into play. If TM research ever really makes a splash in any scientific discipline, you can bet that the system of checks and balances will kick in, and many skeptics will be looking very carefully at the research. (You can believe me that they have made much less of a splash thus far than claimed in their promotional material in in the mass media.) They will try not only to replicate the findings, but also to develop indicators that are sensitive to the sorts of negative effects that are claimed by the smaller, less systematic studies cited on TranceNet and elsewhere.
The thing is, much of the TM research is very non-controversial, and the much smaller volume of potentially controversial stuff that has been published is tucked away in 3rd-rate journals (or worse). So the TM organization can point to the publications and say "Look, we're published in prestigious, main-stream scientific journals!" Most scientists are not interested in trying to counter such hype in the court of public opinion, and most are not interested in following up the breathless claims of TM research because--quite contrary to the way the TM propaganda machine portrays things--the more controversial TM research is widely ignored (even among consciousness researchers who you would expect to be very sympathetic), and the bulk of the rest is pretty mundane from the perspective of journal readers.
I hope this sheds a little light on a complex set of issues.
Dept. of Sociology, University of Iowa
Center for the Study of Group Processes
Member of the Internet Link Exchange